Relief valve and signal for fluid filters



g- 7, 1951 wfs. JAMES 2,563,786

RELIEF VALVE AND SIGNAL FOR FLUID FILTERS Filed March 18, 1949 x 0 08 lo [a ying,

Patented Aug. 7, 1951 RELIEF VALVE AND SIGNAL FOR FLUID FILTERS William S. James,Birmingham, Mich., assignor to Fram Corporation, a corporation of Rhode Island Application March 18, 1949, Serial No. 82,162

3 Claims. 1

This invention relates to a fluid filter, more particularly designed for filtering gasoline. In the filtering of gasoline, it is usual that the filter element be so located that all of the gasoline will pass through the filter in what is usually termed a full flow filter, as distinguished from a by-pass filter. Thus, if such a filter is used in connection with an internal combustion engine and the filtering element becomes clogged by reaching its dirt collecting capacity, no further flow will be had through the filter element. Consequently, the flow of gasoline to the engine will be stopped and it will be necessary to remove the filled filter element in order that the engine may be again started. The removal of the filter for this purpose is not generally known by the user, and consequently it occurs that the engine is out of use until the element may be replaced or removed.

One of the objects of this invention is to provide an arrangement so that should the filter collect sufficient contaminant to become clogged and no longer pass a suificient amount of fluid for the supply of the engine to which it is attached, there will be a relief or valve means open so that fluid may pass to the engine for the supply of the fuel thereto.

Another object of the invention is to provide some indicating means so that should this flow become clogged and the valve means operate, then the user may be notified of the occurrence and thus replace the element with a fresh one for further use.

Another object of the invention is to provide a signal means which will be readily visible through the transparent bowl which is used in connection with a gasoline filter.

Another object of the invention is to provide an arrangement so that the filter element itself acts as the valve means. 7

Another object of the invention is to provide a signal which will be released by lifting of the filter element from its seat in acting as the valve means.

Another object of the invention is to provide some indicating device which will be operated by the movement of the filter upon becoming clogged.

With these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described and particularly pointed out in the appended claims.

In the accompanying drawings:

Fig. 'l is a sectional view through the filter showing the filter element on its seat and the 2 indicating means in normal position for operaion;

Fig. 2 is a view similar to Fig. 1 illustrating the filter element as raised from its seat acting as a valve and releasing the indicating means;

Fig. 3 is a section on line 3-3 of Fig. 1;

Fig. 4 is a perspective view of the indicating means.

In proceeding with this invention, I provide a head and a bowl which is held together by a nut having screw threaded engagement with a head. Within this bowl there is provided a shell through which entering liquid must pass to reach the exit opening in the head. A filter element is positioned in this shell to seat upon a seat in the shell and close the passage therethrough, except that the fluid will pass through the filtering element. An indicating means such as a U-shaped spring whose arms tend to move toward each other is stretched to engage the seat at diametrically opposite points and is held in this position by a coiled spring urging the filter element toward the seat. Thus, should the element lift from its seat, the spring will be released so that its arms will move toward each other, removing at least one of the arms from the seat, allowing the spring either to hang suspended from one of its arms or to drop completely from position, in either of which cases this change of position will be readily visible, to the user.

With reference to the drawings, 10 designates generally a head which is usually a cast metallic material having an inlet opening II which is threaded for connection to a conduit for fluid such as gasoline. There is also provided an exit opening l2 which is similarly threaded for connection to a conduit through which the: filtered fluid or gasoline may pass. This exit opening communicates through passages l3 and M to the center portion of the head, while the inlet opening H communicates through passage I5 to the inner body portion or chamber l6 about the center conduit M of the head. A bowl I1, usually of glass, is flanged as at [8 and is held against a soft packing [9 which is urged toward the under surface of the head by a nut 20 having internal threads 2] which engage external threads 22 on the head.

A shell 25 of thin sheet metal has a slotted flange 26 which is held between the gasket l9 and the under surface of the head and extends downwardly into the bowl as shown in the drawings. The lower edge of this shell 25 is flanged inwardly as at 26' so as to provide a surface for supporting a soft gasket 21 which forms a sealing seat. filter element 30, consisting of a plurality of sheet members rolled into spiral form, is of a size so that its bottom 3! at its outer peripherial edge 32 will engage the soft gasket 2'! and by reason of a coiled spring 33 will be forced against this seat 21 to provide a fluid tight fit to prevent passage of fluid into the shell except that which passes through the filter element 30.

. Spring 33, while engaging on the top of the filter element 30 at one end, also engages a cup 34 which has a downwardly sloping surface and a flange 35 to rest upon the top of the shell flange 26. This flange 35 is provided with a plurality of slots which register with slots in the flange 26 so as to provide for the liquid passing into the bowl as shown by arrow 36. A soft gasket 31 also serves to seal the cup 34 at its upper edge from the entrance flow of liquid into the device.

An indicator designated generally 40 (-Fig. 4) is provided with a pair of arms 4| connected by body 42 with the arms flattened-as at 43 at 'each end. This U-shaped member is spread so that instead of the arms being in the position shown inFig. 4 they will be stretched to the open position shown in Fig. 1 and with the arms so positioned under tension with the parts 43 resting on the soft seat 21 and engaged by the filter element 30 the indicator 40 will be held in place as shown in Fig. 1 by friction between seat 2'! and the bottom 3lof the filter element ,30 under the action of the spring 33.

In operation, the fluid will pass inwardly through the opening "II down through the slots 36 into the bowl H and upwardly into the shell 25 and through the filter 33 and thence out through the conduits l4, l3, and 12. Should the filter-element 30becom'e clogged, the strength of the spring 33 is such that the filter element will lift from its seat 21 to permit the passage of fluid around the outer surface of the filter element 30 which is spaced from its shell 25 and at the same time the indicator 40 being relieved of pressure upon its ends 43 will p'ermit-the-arms 4| to spring toward each other and become displaced from the seat 21, either hanging by one of its arms or dropping completely from position onto the bottom of the bowl. The bowl being transparent, the same will be readily visible so that one looking at the filter will know that the element has become .clogged and is only permitting operation by moving to a by-pass position. Thus, if the filter has been left too long or the contaminant has been unduly heavy, a positive indication is shown that a change should be made.

I claim:

1. ,In a fluid filter, ahead provided with means for the entrance and exit of a fluid to be filtered, a transparent bowl, means to detachablysecure said bowl to said head, means providing a passage all from the entrance through the bowl to the exit, means providing a shoulder along said passage to form'a sealing seat facing the outlet side of the passage, a filtering element in said passage, resilient means urging said element toward the inlet side of the passage against said seat to provide a seal but of a strength toppermit said element to raise off said seat should the element become clogged, a U-shaped member held on said seat by said filter element when in seated position but released when said element is raised from .said seat.

2. In a liquid filter as in claim 1, wherein said U-shaped member has its arms under tension to move toward each other when the filter element is released by its being raised from the seat.

3. In a fluid filter, a head provided with means for the entrance and exit of fluid to be filtered, a transparent bowl, means to detachably secure said bowl to said head, means providing a passage from the entrance-through the bowl :to the exit, means providinga shoulder along said passage toform asealing seatifacing the-outlet side of the passage, a filtering element .in said passage, resilient means urging said-elementttoward the inlet side of the passage against said seat to provide a seal but of a strength to permit said element to raise 011 of said seat should the-element become clogged, an indicator, means to mount a portion of said indicator between said sealing seat andjpart of the element supported by said seat and with another portionof the-I'm dicator depending from said .seat, wherebysaid indicator is released in response to- ,:the .movement of said filtering element from said seat and is dislodged from the :seat by gravity.

-WILLIAM S. JAMES.

.REFERENCES CITED The'following references are of record the file of this patent:

UNITED STATES PATENTS Number Name Date 1,313,929 Sweetland Aug. 26, 1919 1,506,967 Bosworth Sept. 2,?1924 1,805,450 Harvey -1May 12, 1931 1,349,582 Lundborg Mar. 15, 1932 2,145,304 Hill Jan. 31, 1939 2,145,535 Vokes Jan. 31, 1939 2,204,998 Ryan et al June 18, 31 940 2,354,380 Kasten July 25, 1944 2,360,020 .Skinner etal. Oct. 10, 1944 2,412,232 Sutton Dec. 10, 1946 2,439,936 Kasten Apr. .20, 1948 FOREIGN PATEN TS Number Country Date 9,953 Great Britain 1898 

